Feeding and timing mechanism for centrifugal guns.



J. C. PEf- /THER.

FEEDING AND TIMING MECHANISM FOR CBITRIFUGAL GUNS.

APPLICATION FILED JUNKS. 191s.

1L,Q9,5 Patented Dec. 31,1918.

n STATES. FATE 0 'IQE.

J UDSON C. PEW'IHEB, OF WASHINGTON, I JISTRICT OF COLUMBIA, ASSIGNOB TO THE PEW'I'HEB GUN CO., 01 DENVER, COLORADO, A CORPORATION OF COLORADO.

FEEDING AND TIMING MECHANISM FOR CENTRIFUGAL GUNS.

Specification of Letters Patent.

Patented Dec. 31, 1918.

Application med June 5. 1918. Serial 110.238.329.

To an whom it may concern:

Be it known that I, Jonson C. Pnw'rrmn, a citizenof the United States, residing at Washington, in the District of Columbm, have invented certain new and useful Improvements in Feeding and Timing Mecha-.

nism for Centrifugal Guns, of which the following is a specification, reference being had to the accompanying drawings]. j

This invention relates to cent-r1 gal guns, that is, a gun in which projectiles-are e ected by centrifugal action, and particular y to means whereby the discharge of the pro ectile may be timed and thus the direction of the projectile, to some degree, controlled.

One object of this invention is to provide improved meansv for feeding projectiles to the rotating barrel or barrels of the gun and to provide very simple means whereby the time. of discharge of theprojectile into the barrel of the gun may be regulatably con- ..1. trolled so as to thereby control the direction in which the projectiles willbe ejected from the barrels.

A further object is to so construct this feeding and timing mechanism that there will be no chance of the projectile jamming or choking in the passage through which it travels, and in this connection to provide a feedin and timing device so formed that 7 while t e projectile is left free to travel without any chance of jamming or choking, yet it will be positively fed to the point of discharge into the barrel. 7

A further object is to combine with the blades ofan aeroplane propeller, gun barrels rotatable with the blades around the axis of the propeller and provide very simple means whereby the projectiles may be discharged from a hopper. or other source of supply into the chamber and be carried from thence to said barrels, and provide means controllable by the aviator for causing the discharge of projectiles from each barrel as it reaches a certain predetermined point.

Other objects will appear in the course of the following description. A

My'invention is illustrated in the accompanying drawings, wherein Figure 1 is an inside face view of an aeroplane propeller with I'ny centrifugal gun mounted thereon, the feeding and timing mechanism being partly in section;

Fig. 2 is'a section on the line 22 of Fig. 1; r

Fig. 3 is a fragmentary section on the line 3-3 of Fig. 2; 1

Fig. 4 is a diametrical section of the annular collar 26; and

Fig. 5 is a diagrammatic view illustrating the position of a gun barrel at the time of receiving and of discharging the projectile.

Referring to these drawings, 10 designates a shaft or rotatable member which is illustrated as'the shaft of an aeroplane propeller and 11 designates the blades of such a propelbody 12 which, as illustrated, forms apart of the hub of the propeller and is provided with an outwardly extending flange 13 through which bolts 14 pass engaging the clamping plate 15 holdingthe blades of the propeller in place upon the shaft. The

ody 12 is formed with a centrally disposed bore 16 for the shaft 10 and concentric to this bore and upon its outer face the body is formed with a central chamber 17. Exterior to the circumferential wall 18 of this chamber is a circumferential wall l9.spaced from the wall 18 and lower than this wall. The wall 18 is formed at diametrically 0pposite points with outlet openings or ports 20, which are circular in form and which extend down to the bottom of the chamber 17, these ports opening into longitudinally extending grooves 21 formed in the wall 18, these grooves in turn openin at their inner ends into radially extending ports or channels 22. Each exit openin or throat 22 discharges into the enlarge somewhat funnel-shaped inner end 23 of a barrel 24. Two of these barrels are shown attached-to the two blades 11 but I do not wish to be limited to this number or to the use of a plurality of barrels. These barrels 24 are intended to be made of light metal and attached in any manner to the exit edge of a blade.

The peripheral face of the chamber 17, as will be noted from Fig.1 is not concentric to the axis of the shaftlO but is so formed 20, I provide eccentric surfaces 25 by forming the wall 18 relatively thick at each pomt 24 and radually decreasing the thicknesspf the wail from the point 24to the oppos te port 20. Thus the "centrifugal 'actiou wlll cause the projectile to be guided by this eccentric surface 25 to the port 20 and then the stop 24 will prevent the further move-. ment of the projectile circumferentially and the projectile w1ll be thrown out of the port 20 into the slot 21 and the barrel.

It is necessary to provide means for positively feeding the projectiles from the port 20 to the port22 in a path approximately parallel to the axis of the shaft 10. To this end I'dispose around the wall 18 the collar 26, which collar is formed with a flaige 27 engaging in the space between the wall 18 and the body 12. The inner face of this collar 26 as illustrated in Fig. 4 is formed with a relatively shallow spiral groove 28. This groove is approximately two-fifths the depth of the projectile and the flange 27 is cut away as at 29 to provide a termlnatlon of this groove, this termination being slightly beveled outward. This termination29 is the discharge point for the projectile and the position of this termination 29 of the spiral groove determines the direction of discharge of the projectile.- For the purpose of adjustably rotating the collar 26, so that the gun may be aimed, I may provide any suitable mechanism but I have shown for this purpose the collar as formed with exterior gear teeth 30 operatively engaged by a pinion 31 mounted upon a shaft 32 adapted to I be operatedrby hand and carrying a hand wheel 33 for this purpose having thereon a' pointer 34, this pointer being so arranged that when the polnter is pointed at the objective, the gun will discharge in that direction.

While I do not wish to be limited to any particular means for feeding the projectiles into the chamber 17, and any suitable means may be used for this purpose, I have illustrated for this purposea feed chute 35 disposed through the supporting plate 36 extending across the chamber 17 and which plate also supports the shaft 32. This plate 36 may form one of the bearings for the propeller shaft, and in aeroplanes may be inthe form of a brace.

In operation the projectiles are discharged into the chamber 17 from the chute 35 and inasmuch as the body 12 is rotating at a high speed, the projectiles will also be caused to travel around with the body and will be urged radially outward by centrifugal force and will therefore bear against the curved inner face 25 of the chamber 17. When the projectile comes in contact with one of the stops 24, the circumferential movement of,

through the port20 and against the spiral track and hence the projectile will be fed toward the port'22 until the projectile reaches the termination 29 of the track. Here the projectile leaves the track and the centrifugal forcewill carry it into the throat 23 of the barrel 24 and out of the barrel with a force depending upon the speed of rotation of the barrel and the length thereof.

It will be noted that it is only when the throat of the barrel reaches the terminal 29 that a projectile can be discharged into the ba-rreL In effect, the flange 27 of the collar 26 is cut away at the point 29 to thereby leave an opening or gate which, when it alines with the throat 23 permits the discharge of the projectile. It will be obvious, therefore, that the point of discharge of the projectile into the barrel will depend upon the rotative adjustment .of the feeding and timing collar 26. i

Now by reference to Fig.5, it will be seen that if the projectile be discharged into the throat of the barrel When' the barrel is in the position indicated ate, the projectile will be discharged from the barrel when the barrel is in the position b and the projectile-will be discharged in the direction ."of the arrow .0.

The barrel therefore moves through the arc of about 345, before'the projectile is discharged from the barrel. The angular dis-' tance therefore between the radial direction of the cut-away portion 29 and the point at which the barrel is disposed when it discharges is approximately 345. The pointer 34 is, therefore, set at an angular distance of 345 in advance of the terminal portion 29 of the spiral track. Of course this angular distance between. the point of discharge into the ioo barrel and the point of discharge from the barrel reaches a point where the projectile.

on leavingthe barrel will travel toward the objective.

A very vital point of my invention lies in the fact that the distance between the inner end wall of the slot 21 and the crests of the spiral track 28 is greater than the diameter of the projectile, so'that, for instance, were it not for centrifugal force which throws the projectile out against the spiral track, the

projectile would 'roll from the port 20 along the slot 21 to the port 22 without obstruction. ,The projectile, therefore, is only held to the track 28 by centrifugal force and is tile would be liable to bind and the gun would jam. It is only by leaving the projectile perfectly free to move along the track and be discharged therefrom that I secure this freedom from jamming or choking.

It will be seen that the collar 26 provides means for feeding the projectile parallel to the axis or shaft 10 to a point where centrifugal force can carry it into the barrel and also provides means whereby the pointof discharge of the projectile can be prede:

termined v I wish it particularly understood that while I- have illustrated my invention as applied to barrels which are mounted upon and rotatable with the blades of an aeroplane, I do not wish to confine my invention to such-use as the barrels might be rotatedlby any rotatable element, driven by any suitable power, Of course it is 'obvi-.

ous that projectiles cannot be aimed with any extreme accuracy, but nevertheless it is possible, as I have found by careful tests, to predetermine the discharge of projectiles, so as to provide a zone of fire through which the projectiles pass.

It is' to be noted that the slot 21 extends transversely to the thread or track 28 on the annular collar 26-. and that the slot is only wide enough to accommodate one projectile at a time or, in other words, the Width of the slot is slightly greater than the diameter of the projectile. Therefore, only three projectiles can be accommodated at one time in the slot, each one resting in one thread or groove of the track. By no possibility, therefore, can one projectile pass out of the port 22 immediately after or so closely fol lowing another projectile as to cause the projectiles'to choke or jam in the port 22 or in the slot 21. The annular collar 26, therefore, acts to feed the projectiles, time their ejection, and yet hold them in proper spaced relation.

Furthermore, it is to be noted from Fig. 2 that the edge of the flange2-7 at 29 is spaced from the bottom wall of the space a length of approximately four feet, that is, the length of the ordinary propeller blade of a flying machine, but 1t is to be'understood that where the barrel is less than .four feet, a corresponding less angular distance will be required between the point of reception of a projectile: and the point of ejection and that ifthe barrel be over four feet, itvwill require. very nearly a full revolution of the barrel, in order for the pro- 'ectile to travel along the barrel. With a arrel four feet in length, and having 1500 R. P. M., '.the muzzle velocity of the:projectile will be 890 feet per second, if the barrel be straight, that is, radial tothe center of motion, but if the *barrel be curved, to follow the path of movement of the projectile through space as it travels outward from the center to the circumference of the gun, this velocity will be decreased about 40%. In other words, by using the straight barrel I secure an increase o'fabout 40% in the muzzle velocity of the projectile.

Not onlydoes a curved barrel decrease the muzzle velocity of the projectile but there is greater wear both on the projectile and on the barrel where the barrel is curved or spiral than where 'the barrel is radial. Where the projectile is discharged into a straight barrel, without having traversed a spiral course. on a rotor, it is necessary to gradually deflect the projectile so as to decrease 1ts radial movement and eject the projectile at a tangent to a circle concentric to the axis of motion of the rotatable gun and this causes the projectile to strike the barrel at a plurality of points and tends to alterthe shape of the projectile materially and to very shortly wear out and score out .stitutes a continually shifting load. This device is adapted to be used not only with aeroplanes, but also on tanks or as 'a machine gun for close work against masses of enemy; Due to the fact that it is impossible to secure absolute accuracy in the form of the projectiles themselves, in their density or absolute accuracy in the shape of the barrel, it is practically impossible to cause all of the bullets to be ejected at exactly the same point in space and to travel in exactly the same linebut I have found in practice that with barrels four feet long attached to propeller blades, that it is possible, at a dis tance of one hundred yards, to secure a pattern approximately fifteen feet long and a foot wide Within which zone all of the bul lets from the gun will pass. It is, therefore, obvious that if this gun be used on an aeroplane, that'a zone of fire will be created extending'in a plane at right angles to the line 0f flight, which will be very destrucv five at relatively short ranges and is particularly useful in attacking bodies of troops on the ground, and in attacking enemy aeroplanes flying parallel to the plane hav-.

ing a gun of this character mounted thereon. At the present time, it is impossible for two one-seater planes flyin parallel to each other to attack each other, ut with this gun it is possible to attack an enemy aeroplane whether it be above, below or to one sideof the other, when the planes are flying parallel. It is, of course, obvious that the rotata'bly' mounted barrels might be disposed to rotate in a horizontal plane as well as in a vertical plane or in any other plane at an angle to the horizontal.

While I have .illustrated mechanism.

which I believe to be entirely effective for the purpose intended, which has few parts, and which is very simple in its operatlon, yet it will be obviouswthat this mechanism may be modified to suit it to variousconditions, without departing from the spirit of the invention, as defined in the appended claims. v

Having describedmy invention, what I .claim is:

1. A centrifugal gun including a chambered element having a radial barrel,-means for rotating the barrel and element together, the chamber of said element being concentric to the rotative axis of the element and barrel and having a port discharging into the barrel, and means for predetermining the point at which a projectile shall be discharged from the chamber into the barrel including a member disposed concentric the axis of rotation of the chambered element and barrel therewith, and means for predetermining the and having a discharge opening with which the'barrel and port are adapted to aline, said member being rotatably adjustable, but being normally held from rotation. 4

2. A centrifugal'gun including a rotatable chambered element having a. barrel rotatable justably predetermining the point at whicha projectile shall be discharged from the element into the barrel, including a member A having a helical track against which the projectile is urged by centrifugal force, said member being rotatively adjustable relative to the chambered element and the barrel.

- tending. groove into which said port opens,

' port leading from it and the outer face of which the pro ectile shall be discharged from the chambered element into the barrel comprising an annular member disposed between said walls and rotatably adjustable around the axis of the element, saidmember having a port with which the ports in the said walls are adapted'to register, and means for rotata'bly adjusting said member.

5. A centrifugal gun including a rotatable element-having a centrally disposed chamber bounded by an annular wall and having an outer annular wall spacedfrom the first named wall, the inner wall having a radial port leading from it and the outer face of the inner wall having a longitudinally extheouter wall having a port into which said groove discharges, a radially extending barrel into which said second name-d port discharges, and means for carrying projectiles from the first named port to the second named port including an annular member disposed within said Walls and having a spiral groove on its inside face, and an opening at its inner end with which the second named ports are adapted to register.

6. A centrifugal gun including a rotatable element having a centrally disposed chamber bounded by an annular wall and having an outer annular wall spaced from the first named wall, the inner wall having a radial the inner wall having a longitudinally extendlng groove into which said port opens, the outer wall having a port into which said groove discharges, a radially extending barrel into which said second named port discharges, means for carrying projectiles from the first named .port to the second named port lncluding an annular member disposed within said walls and having a spiral groove on its inside face, and an opening at its inner end with which the second named ports are adapted to register, and manually controlled means for adjustably rotating said "member to thereby. angularly adjust the position of the openlng in the member to thereby control the instant of ejection of the projectile from the barrel.

7 A centrifugal gun including a rotatable element having a centrally disposed chamber bounded by an annular wall and havmg an outer annular'wall spaced from the first named wall, the inner wall having a radlal port leading from it and the outer face of the inner wall having a longitudinally extending groove into which said port groove on opens, the outer wall having a port into which said groove discharges, a radially extending barrel into which said second named port discharges, means for carrying projectiles from the first named port to the second named port including an annular member disposed within said walls and having a spiral groove on its inside face, and an opening at its inner end with which the second named ports are adapted to register, the distance between the crests of the spiral track and the confronting face of the inner wall being greater than the diameter of the [projectile 8. A centrifugal gun including a rotatable chambered element having a barrel extending radially outward therefrom and rotatable therewith and disposed in a plane parallel to but offset from the plane of the chamber of the element, and means adjust-- able relative to the barrel and chambered element around the axis of the chambered element as a center for feeding projectiles one by one at uniformly spaced distances from the chamber parallel to the axis 9f the element and into the barrel.

9. A centrifugal gun including a rotatable chambered element having a barrel extending radially outward therefrom and disposed in a plane parallel to but offset from the plane of the chamber ofthe element, means for feeding projectiles one by one at uniformly spaced distancesfr-om the chamber parallel to the axis ofthe element and into the barrel, including a rotatably adjustable collar having an interior spiral groove, the wall of the chamber having a radial port and a longitudinally extending the exterior of the wall into which the port opens, said longitudinally extending groove extending transverse to the spiral groove and discharging into the barrel.

10. The combination with a rotatable shaft, of a body mounted for rotation with the shaft and having radially disposed barrels rotatable therewith, the body having a central projectile containing chamber concentric to the shaft and through which the shaft passes, the shaft forming a central wall for said chamber, and means adjustable with relation to said chamber for directing projectiles from the central chamber, into said barrels.

11. The combination with an aeroplane propeller having radial blades,-of radially disposed barrels carried by the blades, and means constituting part of the propeller receiving projectiles and discharging them into the barrels.

12. A centrifugal gun including a rotatable chamber, a radial barrel rotatable therewith, and a member disposed between the chamber and the barrel and receiving projectiles'from the chamber and discharging them into the barrel, said member having a spiral feed track against which the projectiles are held by centrifugal force.

13. A centrifugal gun including a rotatable projectile receiving chamber, a radial barrel rotatable with the chamber, and means for feeding projectiles one by one at uniformly spaced distances from the chamber into the barrel and controlling the point of discharge of projectiles from the barrel, comprising an annular member disposed between the chamber and the barrel and having a spiral track upon its inside face confronting the wall of the chamber, the bottom of said track being spaced from the 'end of the track disposed in the same plane as the barrel, said member being rotatably.

adjustable around the center of'movement of the barrel.

In testimony whereof I hereunto affix my signature in the presence of two witnesses.

J UDSON -Witnesses:

FREDERIC B. WRIGHT, D. W. GALL.

C. PEWTHER. 

